Some lending companies that take Facebook, Twitter, and other social media profiles into consideration include San Francisco-based LendUp, New York City-based Movenbank, and Atlanta-based Kabbage. "The data we have on customers via social networks says more about them than their FICO," Moven president Alex Sion told the Wall Street Journal. "You can make credit decisions based not on a faceless score, but on who you know."

Furthermore, Laurent Schuller, a spokesperson for Kreditech, which is based in Germany and provides loans in Poland, Russia, and elsewhere, added: "Is someone using an expensive mobile phone like an iPhone or logging in from a web cafe? Is their network on Facebook just drinking buddies from a bar? All of that can be important information."

Yet consumer advocates worry the use of social media could lead financial institutions to unfairly deny credit to borrowers or increase their interest rates. In the case of the aforementioned startups, borrowers voluntarily share their social media pages to improve their chances of approval by providing more data points. But in the world of job hunting, it's not always so clear: A job seeker might never know that he or she was rejected because of a ill-conceived tweet.